Soy-Marinated Beef and Broccoli Skewers

Prepare Marinade: In a small bowl, whisk together soy sauce, hoisin sauce, rice vinegar, honey, minced garlic, grated ginger, red pepper flakes (if using), olive oil, salt, and pepper. Reserve a small portion of the marinade for basting later.
Marinate Beef: Place the thinly sliced flank steak in a shallow dish or resealable plastic bag. Pour the marinade over the steak, ensuring it is evenly coated. Cover or seal and refrigerate for at least 30 minutes to allow the flavors to meld.
Preheat Grill: Preheat your grill or grill pan over medium-high heat. Meanwhile, prepare the broccoli florets by blanching them in boiling water for 2 minutes, then draining and rinsing with cold water to stop the cooking process.
Assemble Skewers: Thread the marinated beef slices and blanched broccoli florets alternately onto the soaked wooden skewers, ensuring each skewer has a balanced mix of beef and broccoli.
Grill Skewers: Place the skewers on the preheated grill. Grill for about 3-4 minutes per side, or until the beef is cooked to your desired doneness and has grill marks. Brush with reserved marinade occasionally during grilling for extra flavor.
Serve: Remove the skewers from the grill and let them rest for a few minutes. Serve hot, optionally garnished with sesame seeds and chopped green onions.